Locking connection for concrete forms



Dec. 15, 1964 w. A. JENNINGS LOCKING CONNECTION FOR CONCRETE FORMS 2Sheets-Sheet 1 Filed Feb. 1, 1963 INVENTOR. W/LL/A M 14. JEN/V/NGSATTOFNEX Dec. 15, 1964 A. JENNINGS 3,160,940

LOCKING CONNECTION FOR CONCRETE FORMS Filed Feb. 1 1965 2 Sheets-Sheet 2III-Ill" \\\-ll// 39 M INVENTOR. W/L L lflM ,4. JENNINGS 6' 7' 7' ORNEXUnited States Patent Ollice 3,160,940 Patented Dec. 135, 1964 3,166,940LOLKKNG CONNECTIUN FGR CGNCRETE FORMS William A. Jennings, Des Moines,Iowa, assignor to Econonly Forms Corporation, Des Moines, Iowa, acorporation of Iowa Filed Feb. 1, 1963, Ser. No. 255,573 2 Claims. (Cl.25-131) This invention relates to metal forms used in making concretestructures and more particularly to a locking connection for releasablyconnecting facing spaced walls of metal forms.

It is the object of the invention to provide an improved lockingconnection having a pin cooperating with a spreader tie used to maintainfacing walls of metal forms in a spaced relationship during the pouringand setting of concrete therebetween.

Another object of the invention is to provide an improved locking pinfor a spreader tie.

A further object of the invention is to provide a releasable lockingconnection which when subjected to vihrations does not unlock theconnection.

Another object of this invention is the provision of a locking pinmovable from one position wherein it prevents a pair of devices fromseparating due to opposed forces, and is itself under a deforming typestress which renders diflicult its removal from the position, to anotherposition wherein its removal is easily accomplished.

An additional object of the invention is to provide a reliable andefficient locking connection which is rugged in construction andeconomical in cost.

vFIG. 1 is a fragmentary perspective view of a plurality of concreteforms shown in assembled relation, embodying the locking connection ofthe invention;

FIG. 2is an enlarged perspective view of the locking I pin of thelocking connection illustrated in FIG. 1;

FIG. 3 is an enlarged longitudinal sectional view taken along the line3-3 of FIG. 1;

FIG. 4 is an enlarged sectional view taken along the line 44 of FIG. 2;

FIG. 5 is an enlarged cross sectional view taken along the line 55 ofFIG. 1 showing the locking pin in its working position; and

FIG. 6 is a view similar to FIG. 5 with the locking ing position.

Referring to the drawing, there is shown in FIG. 1 A

a concrete'form structure indicated generally by the nurneral 10comprising spaced pairs of concrete metal forms 11, 12 and 13 and 14 inassembled positions prior to receiving concrete therebetween. The formsare con ventional, commercially available form units, each having arectangular shape. Each form includes a flat base plate 16, peripheralend flanges 17 and side flanges 17a extended laterally outward from thebase plate 16 and stiffening ribs 13 projected laterally of the baseplate 16 in the same direction as the flanges 17a. The peripheralflanges 17 and 17a are formed with pairs of peripherallyspaced-transverse holes 19 which are circular in cross section. Adjacentforms 13 and 14 are locked together and aligned by a plurality of plateclamps 21, only one of which is shown in FIG. 1. The structure andfunction of the plate clamps .21. are described in detail in patent No.2,870,516, issued January 27, 1959, and entitled Form Unit.

The concrete form structure illustrated base pair of. facing Wallsestablished by the base plates 16 of the respective forms 11, 12 and 13and 14. The transverse space between the facing walls is maintained by aplurality of spreader ties 22, only one of which is shown in FIG. 1. Thespreader ties 22 are releasably fastened at their opposite ends to thefacing forms. Each spreader tie 22 is an elongated flat bar having sidenotches 23 formed therein adjacent each end. As shown in FIGS. 1, 5 and6, each end of the spreader tie 22 has a circular'opening 24 which has adiameter substantially equal to the diameter of the opening 19 in theend flanges 17a.

To accommodate the spreader tie 22, the base plate 16 of a form isprovided at each corner with 'a slot 26 of a size which enables thespreader tie 22 to extend therethrough. A pin retaining means 28 issecured to the base plate 16 and to the end flange 17 adjacent the slot26. The pin retaining means 28 extends in a lateral direction from thebase plate 16 and contains a circular hole 29 in axial alignment withone of the holes 19 in a side flange 17a. The cross sectional dimensionof the hole ,29 is substantially identical to the cross sectionaldimensions of the holes 19 in the flange 17a. The pin retaining means 28has a U-shaped extension 31 defining an outwardly facing slot 32.

The ends of the spreader tie extend through the slots 26 and areconnected to the facing forms 12 and 14 by an L-shaped locking means 33.As shown in FIGS. 2 and 3, the locking means 33 comprises anangular-shaped rod having an elongated curved body 34 forming a firstsection'36 and a second section 37 which terminates in a taperedend 38.The second section 37 is about twice as long as the first section 36 andhas a longitudinal axis which extends upwardly from thelongitudinal axisof the first section at an angle of between three to six degrees.Integrally formed with the end of the first section 36 and projectingnormally therefrom is an arm 39.

7 As shown in FIG. 4, the elongated body 34 of the locking means 33 hasan oval or elliptical shape in cross section, with a majordiameter A anda minor diameter B. The major diameter A is substantially equal to thedi ameter of the holes 19, 24 and 29 of the flange 17a, the spreader tie22, and the pin retaining means 28, respectivelyl When the elongatedbody 34 is inserted through the respective holes, a snug fit orbearingengagement is had between the peripheral surfaces defining themajor diameter A and the adjacent side walls which define the holes 19,24 and 29 in the respective members.

In FIGS. 1 and 3, the locking means 33 is shown in the working positionwherein the arm 39 projects through the slot 32 in the flange 31 and theelongated body 34 projects through the axially aligned holes 19, 24 and29, respectively, in the form flange-17a, the spreader tie 22, and theplate 28. In this position the curved elongated body 34 frictionallyengages an upper sector 41 of the hole 19 in the flange 17 and a lowersector 42 of the hole 29 in the plate 28, 'therebyfrictionally holdingthe locking means 33 in the working position on the metal form 14.

In the working position, the frictional grip of the curved body 34 onthe side walls of the hole 19 in the flange 17a and the side wall of thehole 29 of the pin retaining means 28 inhibits rotation of the body 34;In the pouring and leveling of concrete betwen the forms vibratory andshock forces are imparted to the metal forms. These forces tend torotate the body 34 of the locking means 33 so thatthe arm 39 clears'theslot 32. The longitudinal movement of the body 34 is minimized by thecurved shape of the body as the frictional force between the body 34 andthe side walls of the aligned holes 19 and 29 is increaseduponlongitudinal movement of the body 34, This increase in the frictiongripis caused by the angular shape of the body 34 which must be deformed or bent in order to remove the body from the metal form. 7

Referring to FIG. 5, where the locking means 33 is in the workingposition, the major diameter A extends paral re-used in subsequentlockingv connections.

lel to the longitudinal axis in the same plane as the direction of theforce established by the placement of concrete between the metal formwalls 16, which force is transmitted to the spreader tie 22 by means ofthe locking means 33. In the Working position the arcuate portions 46and 47 of the elongated body 34 are inbearing engagement with theopposed peripheral portions 43 and 44 of the spreader tie 22. Thearcuate portions 46 and 47 are in the same plane as the force F and itsopposite component and thereby take up the lost motion of the lockingconnection. By the same. token,-the opposed peripheral portions 48 and49 of the elongated body 34 at its'minor diameter B are spaced from theopposed arcuate portions 51 and 52 of the spreader tie 22 forming thehole 24. The arcuate side walls 51 and 52 defining the spreader tie hole24 are in a plane normal to the plane of the force F.

' To release the locking joint the locking means 33 is rotated ninetydegrees in the direction of the, arrow, as shown in FIG. 6, by applyinga force to the arm 39. 'In this position the peripheral portions 48 and49 defining the minor diameter B are in the plane of the force F of thespreader tie 22 and is' I claim: v V 1. A locking connection forreleasably connecting a V mold form having a flange formed with acircular hole and aplate extended substantially parallel to the flangewhereby substantially all lateral stress on the elongated body 34 in theplane of the force F is removed. The elongated body 34 is removed fromits inserted or working positionby striking the end 38 thereof with ahammer to overcome the frictional fit of the curved body with the sectorWalls defining the holes 19 and 29 of the flange 17a and pin retainingmeans 28 respectively.

The removal of the elongated body 34from the hole 24 in the spreader tie22 is not impeded by the deformation of the peripheral portions 46 and47 of the elongated body caused by the vibratory and static forcesapplied thereto by the spreader tie 22. These deformed'portions arerotated away and out of engagement with the arcuate pegiois 43 and 44 inthe plane o'f'the stress, as shown in In use, the spreader tie 22positioned to extend bei n tween the walls 16 of facing forms 12 and 14withthe ends of the ties-projecting through the slots 26." In thisposition the ends of the tie are between the end flange 17a and the pinretaining means 28 with theholes 19, 24 v and 290i the respectivemembers in axial alignment. The locking means 33 in the rotatedposition, as shown in FIG. 6, is coupled with the form and tie 22 byinserting or driving the end 38 through the hole 29 in the plate 28, thehole 24 in the end of the tie 22', and the aligned hole 19 in the endflange 17a. After the locking means 33 has been driven, by the use'of ahammer, into frictional ent gagement with the sector of the side walldefining the hole 19 in the flange 17a and the sector of the side walldefining the hole 29 of the pin retaining means 28, the arm 39 isrotated downwardly ninety degrees into the slot 32 of the pin retainingmeans 29 thereby moving the I V 7 major diameter A of the ,curvedbody 34in the plane of the force F to provide a secure connection between thespreader tie 22 and the associated-metal form. t

In order to release the locking connection, the body 34 of the lockingmeans 33 isrotated ninety degrees by applying an upward force to the arm'39'thereby moving the arm 39 out of the slot 32in the flange 31 of thepin retaining means 28. The e10ngated1body134 is' forced back out of thealigned holes 19,24 and 29 respectively, by an impact blow by a hammeron the end 38. The locking means-33 is not destroyed in use and isrepeatedly Although a preferred embodiment has beenldisclosed 7 herein,the invention is not to be so" limited as various 7 modifications,changes in form, and details otthe appara-' tus illustrated may be madeby' those skilledin the, art,

and formed with a circular hole positioned in axial alignment with thehole in the flange with a spreader tie projected laterally from theform, said tie having an end section positioned between the flangeandplate, said end section formed with a circular hole having substantiallythe same diameter as the hole in the flange comprising: (a) an elongatedrod member having a first section projected through the'hole in theplate and spreader tie, and asecond section projected through the holein the flange, the longitudinal axis of said second section beingangularly disposed'from the longitudinal axis of said first section soas .to hold the first section andsecond section in' tight frictionalengagement with opposite portions of the peripheral walls defining theholes in the plate and flange, (b) said elongated member having anoval-shaped cross. section" with a major diameter substantially equal tothe diameter of the hole in the spreader tie and a minor diameterlessthan the, diameter of said major diameter, and (c) means attached to;the end of the first section of ,the elongated member providing an armusable to rotate said member along the longitudinal axis thereof topositio'nthe major diameter of the rod member substantially parallel tothe direction of the force applied to the spreader tie therebysubstantially eliminating lost motion between the spreader tie and rodmember. 2. In' combination, 1 r 1 (a) a" mold form having a lateralflange formed with a circular .hole and a plate extended substantiallyparallel to the flange and formed with'a circular hole positionedin'axial alignment with the hole in the flange, t (b) a spreader tiepositioned between the flange and plate and projected laterally fromsaid form, said 7 tie being formed with a circular hole havingsubstantially the same diameter as the'hole in the flange, "(0) anelongated rod member having a first section projected through the holein the plate and spreader tie and a second section projected. throughthe hole in the flange, the longitudinal axis of said second sectionbeing angularly disposed from the longitudinal axis of said firstsection so as to hold the first section a'ndsecond section in tightfrictional engagement with opposite portions of the peripheral wallsdefining the holes in theplate and flange, I (d) said elongated memberhaving an oval-shaped cross sectionwith a major diameter substantiallyequal to" the diameter otr the hole in the spreader tie and a minordiameterless than the diameter of said major diameterpand V q I i (e)means attached to the end of the first sectionof the elongatedmemberr'providing an 'arm usable to "rotate said member'alo'ng' thelongitudinal axis thereof topo'sition the major diameter of' the rodmember substantially parallel to the direction of the force applied tothe spreadertie thereby eliminating lost motion between the spreader tieand rod member.

References Cited by the Examiner UNITED STATES PATENTS 8/20 fSchub e25-131 4/38 Jennings 25131 3/39, Jennings 25-,131

FOREIGN'PATENTS 162,668 5/55 Australia. 7 MICHAELV. BRINDIS'I, PrimaryExaminer.

2. IN COMBINATION, (A) A MOLD FORM HAVING A LATERAL FLANGE FORMED WITH ACIRCULAR HOLE AND A PLATE EXTENDED SUBSTANTIALLY PARALLEL TO THE FLANGEAND FORMED WITH A CIRCULAR HOLE POSITIONED IN AXIAL ALIGNMENT WITH THEHOLE IN THE FLANGE, (B) A SPREADER TIE POSITIONED BETWEEN THE FLANGE ANDPLATE AND PROJECTED LATERALLY FROM SAID FORM, SAID TIE BEING FORMED WITHA CIRCULAR HOLE HAVING SUBSTANTIALLY THE SAME DIAMETER AS THE HOLE INTHE FLANGE, (C) AN ELONGATED ROD MEMBER HAVING A FIRST SECTION PROJECTEDTHROUGH THE HOLE IN THE PLATE AND SPREADER TIE AND A SECOND SECTIONPROJECTED THROUGH THE HOLE IN THE FLANGE, THE LONGITUDINAL AXIS OF SAIDSECOND SECTION BEING ANGULARLY DISPOSED FROM THE LONGITUDINAL AXIS OFSAID FIRST SECTION SO AS TO HOLD THE FIRST SECTION AND SECOND SECTION INTIGHT FRICTIONAL ENGAGEMENT WITH OPPOSITE PORTIONS OF THE PERIPHERALWALLS DEFINING THE HOLES IN THE PLATE AND FLANGE,